Design Of Switched Reluctance Drive System Based On DsPIC

Switched reluctance drive system is a new mechatronic speed control system, for its satisfactory speed performance and low cost, it has been widely used in precision manufacturing, aerospace, mining machinery, electric vehicle drive and other fields, it is internationally recognized as a highly competitive speed control system.In this paper, the main content is to design a 7.5kw three-phase 12/8 poles switched reluctance drive system. Analyze the working principle of SR motor, the motor basic electromagnetic structure, power and torque, and give the ideal mathematical model of SR motor. Design the hardware circuit which uses dsPIC33FJ128MC706 as the main control chip, then divide into drive, power supply, control and protection four parts, and describe them in details. Write the corresponding software program based on the hardware and achieve the various functions of the system.According to the switched reluctance motor drive starting and braking performance requirements, develop a comprehensive strategy for starting and braking control. In the starting process, use speed and current dual-loop PI control regulation, give the initial values to speed loop integral term and set the appropriate parameters PI, to achieve the best starting performance by controlling the starting current. In the braking process, adopt one phase and three-phase brake combining control strategy, use three-phase braking at high speed, when the speed drops to a certain value, use one phase braking, this control strategy reduces the speed quickly and it also avoid the risk of RP-start after the motor stops.When the motor runs, use fixed-angle and variable angle combining control strategy, at different speeds, give the best angle of commutation logic through changing opening and shutting angles, achieve the commutation of regional. Achieve the point of breakdown totally through software, and this can help reduce the whole system cost.Debug the hardware and software and get the corresponding experimental data, then analyze the experimental results to verify the rationality of the system design.